Too much light

[MayoBoy]

Would two 175 MH lights over an 18" x 18" x 18" be too much?

LPS, zoas, rics, a few SPS.

 

[kiknchikn]

18" x 18" x 18" = 25 gallon tank right? That would be 14 watts/gallon.

I'm not an expert, but that sounds pretty excessive to me. You'd probably melt any rics/zoos in there. Plus you'd probably need a chiller to keep the tank cool enough.

"High intensity" for reef tanks is usually considered 5 - 8 watts per gallon I think...

 

[JimBob Schmidt]

i have a 250w 14k over my 22gal cube, but the light is 12 inches off the water, and im only keeping stuff like sps and clams, i think 2 175 watts might be a bit over kill even for the most light demanding corals.... mayb try just 1 250 watt? it could probably be done (the 2 175's) but the heat issue would be my main consern

 

[MayoBoy]

I'm considering taking down my current system and using the bits and pieces to make a smaller system. Right now I have a 2x175 so I was wondering about re-using it.

 

[JimBob Schmidt]

what color tempurature are the bulbs? if they are 10k (maybe even higher) you could get away with just one light. but you probably could sneek by using 2 175w by setting them on timers so they only overlap each other for like 2 hours to help reduce the heat. i think if u dont want to buy a new fixture just start out with one light and if the livestock isnt happy throw the other light over the tank aswell. just my 4cents

 

[MayoBoy]

One's a 10K XM, the other's a 15K Iwasaki. They're on separate switches and cords so I could just use 1 and have a backup in case the first ballast craps out or something.

Or I could see if I could trade it to someone for a single 250.

Thanks

 

[Amphiprionocellaris]

You could easily get by with only one 175 W, and you could probably use any color you wanted. If you wanted to use both, you probably wouldn't run into too much trouble, but you would likely have to elevate the fixtures for both light and temperature considerations (and probably need a chiller), and you're doubling your costs as far as electricity and bulb replacement.

 

[bigmayreefer]

Ive seen pics somewhere of a 400W mh over a 29g before. It looked pretty good-but it was all sps. I think if you keep the two lights 12 inches above the surface you should be ok- I run a 250 over my 29 with no heat problems. I would experiment and see what happens- you can alway just leave one off if you have too.